Technique of mobile bony island for cochlear implantation in children

The technique of mobile bony island is designed to form a buffering platform for the receiver/stimulator device of cochlear implant. It is especially suitable for young children, in whom the skull is thin and the protrusion of the device would otherwise be significant. This technique was used in 6 cases with an age range from 2 to 12 years old. After the inverted U-shaped postauricular incision and the elevation of the skin/periosteal flap were carried out, the mobile island of bone was drilled in the temporo-parieto-occipital region with a fine diamond burr. This thin island of bone lies on the dura with its edge 0.8-1.0 mm apart from the surrounding bone. The receiver/stimulator device MED-EL COMBI 40+ was positioned on the floating bony seat, and could be recessed 1.5-2.5 mm under slight pressure. This 'floating island of a bony seat' could reduce the protrusion of the device and provide a degree of protection from trauma.